Hot-gas reciprocating apparatus



Jan. 26, 1965 R. J. MEIJER HOT-GAS RECIPROCATING APPARATUS 3 Sheets-Sheet 1 Filed March 5, 1964 FIG.2

INVENTOR.

ROELF J. MEUER AGENT Jan. 26, 1965 R. .1. MEIJER HOT-GAS RECIPROCATING APPARATUS 3 Sheets-Sheet 2 Filed March 3,

INVENTOR.

ROELF MAEUER AGENT Jan. 26, 1965 R. AMELIER Q 3,166,911

HOT-GAS REdiPRocATING APPARATUS Filed March :5, 1964 5 Sheets-Sheet s INVENTOR ROELF J. MEUER .5; Awe. K. AGENT United States Patent 3,166,911 HOT-GASRECIPROCATING APPARATUS Roelf-Jan Meiier, Emmasingel, Eindhoven, Netherlands, assignor to North American Philips Company, Inc,

New York, N.Y., a corporation or Delaware Filed Mar.'3,1'964, SerkNo. 349,113 Claims'priority, application Netherlands, Mar. 11, 1963,

290,975 6 Glaims. (Cl. 62- '6) Theinvention relates'to a hot-gas reciprocating apparatus comprising one ortmore cylinder spaces in each of which a displaceriand a piston are adapted to reciprocate with arelative phase difference so as to vary the volumes of an expansion space anda compression'space. In the operation of the machine, 'these spaces have difierent mean temperatures andcommunicate with each other by meansof a'first heat exchanger (heater), a regenerator and asecond heat exchanger (cooler). Theregenerator is subdivided into a:plurality of regeneratorelements arranged parallel toeach other, while the second heat exchanger is subdivided into a number of-parallel-arranged elements equal to thatof the regenerator.

For the purpose ofthis-specification, the term hot-gas reciprocating apparatus is defined to include not only a hot-gas engine, but also a cold gas refrigerator and a heat pump operating according to the'reversed hot-gas engine principle.

In known apparatus of the said kind, the regenerator is. arranged with an 'initialntension'in arthin-walled housing which in turn is accommodated in a'further housing.

This construction suiiersfrom the limitation that, if no further precautions are taken, upon the passage of the Working medium through the regenerator alternately in one and in the other direction, the regenerator tends to -follow the movement of the medium and strikes the end faces of the housing.

housing. This-impairs the appearance and simplicity of the constructionywhile this spring increasesthe dead space. This adversely affects theefiiciency of the apparatus.

The invention has'for its object to obviate the above disadvantages'and the apparatus is characterized in that each element of the second heat' exchanger is accommodated together with a regener'atorfelement in one housing, the axial inner dimension of the-housing in which an element of the second heat exchanger, which'heat exchanger isconstructed rigidly in the axial direction, and the associated elastically compressible regenerator ele 'me'nt are accommodated, beingsmallerthan the sum of the axial dimensions of the two elements when disassembled.

In the construction in accordance with the invention, the regenerator is consequently compressed more strongly while being mountedtin the housing, while after mounting the regenerator filler material itself ensures that the regenerator does not move in the housing.

'Anadvantageous embodiment of the hot-gas reciprocating apparatus in accordance with'the invention is characterized in that 'each' regenerator element consists'of a filler material accommodated in a further housing which, at its 'sidefacing the associated element of the second heat' exchanger, embraces a rim of the said-element in a flexibility to these pipes. :stresses occurring-in the structure are absorbed by the ice apparatuscomprises more than-one cylinder space, is

characterized in that the-housings associated with a given cylinderspace, in eachof which a regenerator element and an element of the associated secondheat exchanger are accommodated, arearranged in two groups around the-cylinder space concerned, one group being situated on onerside and'the other; group on the other side of the plane, passing through the longitudinalaxes of the cylinder'space concerned. This embodiment is of particular importance. when the-hot-gas reciprocating apparatus is to be accommodated in a small space. The distance between the longitudinal-axesof two adjacent cylinder spaces can then be smaller than in the case of a regular arrangement .of the cooler-regenerator units around the cylinder spaces.

An even more compact structure of the hot-gas reciprocatingapparatus in'accordance-with the invention is characterized infthat, while the housings of the two groups are situated pairwise diametrically opposite each other, the two housings ofeachgroup farthest remote from each other are alt-different distances from the plane passing through the longitudinal axes-of the cylinder spaces.

these pipesabeing connected'to an "annular duct to which further. pipes are, connected through which this duct communicates with the expansion space, is characterizedin that each of the pipes of the first heat exchanger'contains an expansion member which imparts a certain axial As a result the temperature expansion member.

According to. a further favourable embodiment, the expansion member is constituted by a'portion of the pipe which extends transversely to the longitudinal axis of the relevant cylinder space.

In order that the invention may be readily carried into efr'ect;embodimentsxthereof, will now-be 'described;by way ofexample, With'reierence tothe accompanying drawings, in which:

FIGS. 1 and 2 are-an axial section and-a cross-section taken'on. the line 'IL-II, respectively, of a-hot-gas reciprocating apparatus in accordance with'the invention only that part of the apparatus being shown which consists of the-cylinder and the piston and displacer adapted toreciprocateither'ein, and of the first heat exchanger and the second-heat exchanger'with the interposed regenerator,

FlGS.3a andBb show a cooler-regenerator unit inthe demollnted state and in the mounted state, respectively.

FIG. 4Sl'1OWS diagrammatically a possible arrangement of the cooler-regeneratoraunits' around :the cylinder spaces.

FIGSJS and6 are an elevation and-aycross-section taken on the 'line'-VIVI respectively, of a further embodiment of a' hot gas reciprocating apparatus.

In the embodiment'shown .in FIGS. 1 and 2, reference numeral 1 denotes the cylinder wall the upper side of which terminates in an end face 2. Pipe portions 3 of the :heater open-into the conicalpart of'the head'face.

The upper ends of these pipe portions 3 are connected to anannular duct 4. This annular duct 4 constitutes the connection" between the pipe portions 3 and heater pipe 3 portions 5. For the sake of clarity, only two sets of the heater pipes 3 and 5 are shown; in actual fact together they enclose a cylindrical space 6 which serves as a combustion chamber. A burner is placed in or above this space.

With the aid of means (not shown}, a displacer 8 and piston 9 are adapted to reciprocate in the cylinder 1. The heater pipes 5 are also connected to the coolerregenerator units 10. The structure of these units will be described more fully with reference to FIGS. 3a and 31:. Through a connection pipe ll, the cooler-regenerator units 1% communicate with the cylinder 1. As is apparent from the figures, the heater pipes S are provided with a portion 12 extending transversely to the longitudinal axis of the cylinder. This heater pipe portion 12 imparts a certain flexibility to the heater pipes 5, so that, when the distance between the upper ends of the cooler units 16 and the annular duct 4- is increased as a result of temperature differences, no fracture will occur in the apparatus.

FIG. 3a shows a cooler-regenerator unit comprising a cooler portion 13 and a regenerator portion 14. The cooler portion '13 comprises a plurality of pipes 15 the lower ends of which are secured in a flange plate lid and the upper ends in a plate 17 the upper side of which is provided with a flanged rim 18. The regenerator portion 14 comprises a thin-walled housing l? which is closed at its upper end by a plate 2%) provided with a plurality of holes 21. The housing 19 further comprises filler material 22. This filler material may consist, for example, of a plurality of stacked gauzes. The filler material 22 is bounded on its lower side by a sieve plate 23. The lower end of the housing 1% is crimped over a the flanged rim 1?. The filler material 22 and the sieve plate 23 are accommodated in the housing 19 so that a slight movement in the axial direction with respect to the housing is possible. The housing is can slide over the flanged rim 18. In the demounted state shown in FIG. 3a, the assembly of cooler and regenerator has an axial length A PEG. 3b shows the cooler-regenerator unit in the mounted state. The cooler-regenerator unit is accommodated in a housing 4% to the upper end of which one or more heater pipes 5 are connected. The plate of the regenerator -14 engages the shoulder 24 of the housing 4%. The housing 40 is closed at its lower end by a closing member 25 which in the embodiment shown in FIG. 3b is soldered in the housing. The closing member 25 may also be connected to the housing 4G by a screwed connection or in a difierent manner. The cooler-regenerator unit 13, 14 is enclosed between the shoulder 24 and the upper edge of the closing member 25, the distance between the shoulder 24 and the upper edge of the closing member 25 having a dimension A which is smaller than the length A of the cooler-regenerator unit in the demounted state. As a result of this smaller dimension A the filler material 22 is slightly compressed, while the housing 19 has slid over the rim 1%, so that, as is apparent from figure, there is a certain amount of clearance between the crimped edge of the housing 19 and the lower surface of the rim 18. An inlet 26 and an outlet 27 for the cooling liquid also communicate with the housing 4! Consequently, the cooling liquid flows around the pipes 15, while O-shaped rings 28 ensure satisfactory sealing. The closing member 25 has a recess 30 through which the pipes 15 communicate with the connection pipe 11 which connects the coolerregenerator .unit to the space in the cylinder 1.

'The compression of the filling mass 22 can be increased or decreased at will by interposing one or more rings between the upper edge of the closing member 25 and the plate 16 of the cooler 13. It should be appreciated that these rings may also be provided between the shoulder 24. and the plate 25? of the regenerator 14. FIG. 4 shows diagrammatically an embodiment of a hot-gas reciprocating apparatus in which the cooler, re generator units i are arranged in two groups of three, one group on either side of the plane passing throughthe longitudinal axes of the cylinder spaces. The figure clearly shows that the distance B between the longitudinal axes of the two cylinders is smaller ban in case the units 3.3 are arranged arbitrarily around the cylinders, as shown in H63. 1 and 2. A further decrease of this distance is obtained when the units it? are arranged around the cylinders in the manner shown in F185. 5 and 6. In these figures, two cylinders 3i and 32 are shown. Two groups of regenerator-cooler units are arranged around the cylinder 31. The regenerator-cooier units 33, 342-, 35 are located on one side of the plane passing through the longitudinal axes of the cylinders 31 and 32, whilst the other group of re enerator-cooler units 36, 37, 38 co-operating with cylinder 3!; are located on the other side of that plane. it is apparent from the drawing that the regenerator-ccoler units of each group most remote from each other are located at different distances from the plane passing through the longitudinal axes of the cylinders. The units 33 and 33 located diametrically opposite each other are closer to the plane passing through the longitudinal axes of the cylinders than the units 35 and 36 likewise located diametrically opposite each other. The same holds for the units connected with the cylinder 32. in this manner, an extraordinarily compact, s tort structure of a hot-gas reciprocating apparatus is obtained.

Finally, it is again clearly apparent from FIG. 5 that the heater pipes 5 for part of their lengths extend transversely to the longitudinal axis of the cylinder with which they co-operate. From this figure also appears the advantage that the length of the transversely extending portions of the heater pipes is greater according as the heater pipe has a larger dimension between the point at which it communicates the annular duct 4 and its connecting point to the coolcr-regenerator unit.

What is claimed is:

l. A hot-gas reciprocating apparatus comprising at least one cylinder having a compression space and an expansion space, a displacer and a piston adapted to reciprocate in said cylinder with a relative phase difference and to vary the Volumes of said compression and expansion spaces, said spaces being at different mean temperatures during operation of said apparatus, means connecting said spaces and including a heater, a cooler a regenerator, said regenerator being subdivided into a plurality of substantially parallel-arranged regenerator elements, resiliently compressible in the axial direction, said cooler also being subdivided into a plurality of substantially parallel-arranged axially rigid elements equal in number to the number of said regenerator elements, a main housing, each element of said cooler being accorn modated together with a regenerator element in said housing, the axial inner dimension of the housing containing said rigid cooler elements and compressible regenerator elements being smaller than the sum of the axial dimensions of any of said cooler elements and corresponding regenerator elements in their demounted state.

2. A hot gas reciprocating apparatus as claimed in claim 1 wherein each regenerator element is constituted of a filler material and said cooler element is provided with a rim, a second housing enclosing said regenerator element, said second housing on its side facing the associated cooler element embraces said rim on the cooler element in a manner such that said second housing located in said main housing and cooler element are movable with respect to each other under the influence of axial forces thereon.

3. A hot gas reciprocating apparatus as claimed in claim 1 wherein regenerator elements and associated cooler elements are arranged in two groups around said Cylinder space, one group being located on one side 5 and the other group on the other side of the plane passing through the longitudinal axis of said cylinder space.

4. A hot gas reciprocating apparatus as claimed in claim 3 wherein the housings of said two groups are located pairwise diametrically opposite to each other while the housin s of each group most remote from each other are located at different distances from the plane passing through the longitudinal axes of said cylinder spaces.

5. A hot gas reciprocating apparatus comprising at least one cylinder having a compression space and an expansion space, a displacer and a piston adapted to reciprocate in said cylinder with a relative phase difference and to vary the volumes of said compression and expansion spaces, said spaces being at diiferent mean temperatures during operation of said apparatus, means connecting said spaces and including a heater, a cooler and a regenerator, said regenerator being subdivided into a plurality of substantially parailel-arranged regenerate: elements, resiliently compressible in the axial direction, said cooler also being subdivided into a plurality of substantially parallel-arranged axially rigid elements equal in number to the number of said regenerator elements,

a main housing, each element of said cooler being accommodated together with a regenerator element in said housing, the axial inner dimension of the housing containing said rigid cooler elements and compressible regenerator elements being smaller than the sum of the axial dimensions of any of said cooler eiernenta and corresponding regenerator elements in their dernounted state, an annular duct, a plurality of pipes being part or" said heater, one end of each of said pipes being in communication with said housing, the other end of each of said pipes being in communication with said annular duct, said annular duct being provided with further ducts for communication with said expansion space, and each of said pipes or" said heater including an expansion member.

6. A hot gas reciprocating apparatus as claimed in claim 5 wherein said expansion member is constituted by a portion of the pipe extending transversely to the longitudinai axis of said cylinder space.

References Cited in the file of this patent UNITED STATES PATENTS 2,963,871 Meijer Dec. 13, 1969 

1. A HOT-GAS RECIPROCATING APPARATUS COMPRISING AT LEAST ONE CYLINDER HAVING A COMPRESSION SPACE AND AN EXPANSION SPACE, A DISPLACER AND A PISTON ADAPTED TO RECIPROCATE IN SAID CYLINDER WITH RELATIVE PHASE DIFFERENCE AND TO VARY THE VOLUMES OF SAID COMPRESSION AND EXPANSION SPACES, SAID SPACES BEING AT DIFFERENT MEANS TEMPERATURES DURING OPERATION OF SAID APPARATUS, MEANS CONNECTING SAID SPACES AND INCLUDING A HEATER, A COOLER AND A REGENERATOR, SAID REGENERATOR BEING SUBDIVIDED INTO A PLURALITY OF SUBSTANTIALLY PARALLEL-ARRANGED REGENERATOR ELEMENTS RESILIENTLY COMPRESSIBLE IN THE AXIAL DIRECTION, SAID COOLER ALSO BEING SUBDIVIDED INTO A PLURALITY OF SUBSTANTIALLY PARALLEL-ARRANGED AXIALLY RIGID ELEMENTS EQUAL IN NUMBER TO THE NUMBER OF SAID REGENERATOR ELEMENTS, A MAIN HOUSING, EACH ELEMENT OF SAID COOLER BEING ACCOMMODATED TOGETHER WITH A REGENERATOR ELEMENT IN SAID HOUSING, THE AXIAL INNER DIMENSION OF THE HOUSING CONTAINING SAID RIGID COOLER ELEMENTS AND COMPRESSIBLE REGENERATOR ELEMENTS BEING SMALLER THAN THE SUM OF THE AXIAL DIMESIONS OF ANY OF SAID COOLER ELEMENTS AND CORRESPONDING REGENERATOR ELEMENTS IN THEIR DEMOUNTED STATE. 